1. Field of the Invention
The invention relates to a method and an appliance for cooling a gas turbine combustion chamber cooled by means of impingement and convection cooling or pure convection cooling.
2. Discussion of Background
In modern gas turbine combustion chambers, cooling methods which require little or, indeed, no cooling air are increasingly being used. Because NO.sub.X emissions have to be avoided as far as possible, efforts are made to pass as much air as possible through the burner. For this reason, combinations of impingement and convection cooling systems or pure convection cooling systems are employed with ever increasing frequency. In the case of an unfavorable design, such systems can have the problematic property that small primary damage, for example a small hole in the combustion chamber wall, can lead to very large consequential damage which endangers the operation of the gas turbine. As an example, a hole in a cooling duct can lead to the cooling duct being inadequately supplied with air downstream of the hole. This can lead to damage to the whole duct downstream of the hole or even to more extensive damage.